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Harlequin Frog – Istockphoto

March 1, 2018. Life / Back from the Brink

Variable Harlequin Frog Conservation

Russell A. Mittermeier, Anthony B. Rylands, Wes Sechrest, Penny F. Langhammer, John C. Mittermeier, Michael J. Parr, William R. Konstant, Roderic B. Mast

Amphibians are survivors, having endured four mass extinction events on our planet. But conditions over the past three decades have put them at the forefront of another impending mass extinction, with 41% of more than 7,000 described species currently threatened. The striking Variable Harlequin Frog epitomized the loss of amphibians worldwide, from Central America to Australia, when it disappeared suddenly from Costa Rica and Panama in the early 1990s.

Censuses conducted in 1982–1983 at Monteverde reported an average of 751 adult harlequin frogs along a 200-meter transect; a decade later, surveys failed to detect a single frog. After the last individual was seen in 1996, the once-common species was believed extinct.

But then, in 2003, a young herpetologist, Justin Yeager, was studying poison dart frogs in Costa Rica when his guide mentioned a yellow and black frog living in the rainforest. Yeager assumed the guide was mistaken. Two days later, the guide appeared holding a pair of Variable Harlequin Frogs. A breeding population of the harlequin frog was discovered in the Pacific foothills of the Talamanca Mountains in Costa Rica in 2008, and research began to give us an understanding as to what set these populations apart from all those that had succumbed around them. The reappearance of the harlequin leads us to ask: What other species presumed extinct might be hanging on?…

Conservation Status: Critically Endangered


This is an excerpt from the CEMEX Nature Series volume BACK FROM THE BRINK (2017)


Back from the Brink

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